The present invention relates to a planetary gear train.
A planetary gear train has a carrier with a plurality of pinions, a sun gear located at the center thereof and biting with the pinions and a ring member disposed so as to surround them and biting with the pinions in general. Among them, the carrier has two carrier plates and comprises a carrier case for supporting pinion shafts that rotatably support the pinions from both sides by extending and securing carrier bridges from one carrier plate to the other carrier plate.
Such a planetary gear train is used as a power distributing planetary gear train in Japanese Patent Laid-Open No. 2004-353780, for example. The carrier is formed in a body with an input shaft that is connected with an internal combustion engine, the sun gear is linked with a first motor for primarily generating electricity and the ring gear is linked with a driving shaft that is connected with an output shaft, respectively. Power is thus distributed from the internal combustion engine to the first motor and the driving shaft and part of the power of the internal combustion engine is transmitted to an oil pump disposed on a shaft parallel with the input shaft (below the power distributing planetary gear train) by the ring member secured to an outer edge of the carrier plate that is the root of the carrier bridge.